Encased innerspring mattress and method of making same

ABSTRACT

A method of making a foam encased innerspring mattress and an innerspring mattress made according to the method. The method includes the steps of assembling the sides and bottom of a foam housing, positioning an innerspring unit in the housing, securing a foam layer to the top of the housing, and sealing the innerspring unit therein. A quilted covering is applied over the completed assembly. According to the method, a foam encased innerspring mattress can be made in any desired firmness, and any desired size or shape, including standard bedding sizes and shapes.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention:

[0002] The present invention generally belongs to the field of innerspring mattresses. In particular, the present invention pertains to foam encased innerspring mattresses.

[0003] 2. Discussion of the Related Art:

[0004] The process of constructing affordable and comfortable bedding has long been a necessary but time-consuming endeavor. Many steps are required to obtain the quality of mattress desired by consumers, and the manufacturing steps often require painstaking precision and labor-related expense on the part of the manufacturer.

[0005] Furthermore, completely different tooling and manufacturing steps were required whenever there is a need to construct a mattress in the various standard mattress sizes, such as king size, queens size, twin size, etc. The difference in these various sizes, even though they are standard sizes, tends to require an inordinate amount of attention on behalf of the manufacturer, because of the level of careful attention to detail and precision required for each size of mattress produced.

[0006] Moreover, whenever there is a need to manufacture a mattress that is non-standard in size, or that is built according to a custom order, the manufacturer once again must expend significant amounts of time and attention to produce mattresses that meet this demand. Often times, the manufacturer's investment in taking on this expense is lost over time because there may not be further demand for another mattress meeting the same custom specifications.

[0007] In addition to building mattresses according to custom specifications, there is often a demand for mattresses that are arranged in novelty shapes, such as round, oval, heart-shaped, etc. Such novelty shapes, due to the fact that they are anything other than a traditional rectangular flat bed, require unusually large amounts of time expenditures and labor costs. The time expenditures and labor costs are generally related to tooling-up for significant productions run and implementing reliable quality assurance measures. Unfortunately, as has been stated above with respect to mattresses manufactured according to custom specifications, the investment by the manufacturer with respect to producing novelty shaped mattresses may never be recovered once demand for such novelty shaped mattresses diminishes.

[0008] Thus, constructing a comfortable and reasonably priced mattress capable of satisfying the tastes of a wide range of consumers has long been the aim of many bedding manufacturers.

[0009] Accordingly, the present invention solves these problems in a simple, cost-effective and straight-forward manner.

SUMMARY OF THE INVENTION

[0010] It is an object of the present invention to provide a method for making a foam encased innerspring mattress and a mattress made according to the method.

[0011] It is a further object of the invention to provide a method of making a foam encased innerspring mattress that is cost effective and simple.

[0012] It is an additional object of the invention to provide a foam encased mattress that is economical to purchase and that provides restful sleep.

[0013] It is yet another object of the invention to provide a foam encased mattress that can be assembled using only a few parts.

[0014] It is yet a further object of the invention to provide a foam encased mattress that can be assembled with relative easy and with a minimal investment in labor.

[0015] It is yet an additional object of the invention to provide a foam encased mattress that can be made available in any desired firmness.

[0016] These and other objects of the invention will become apparent upon careful review of the following detailed description of the preferred embodiments, which is to be read in conjunction with a review of the appended drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 shows a foam encased mattress according to the present invention;

[0018]FIG. 2 shows a method step according to the present invention;

[0019]FIG. 3 shows an exploded view of a foam encased mattress according to the present invention;

[0020]FIG. 4 shows a sectional view of a foam encased mattress according to the present invention; and

[0021]FIG. 5 shows a cut-away view of a foam encased mattress according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022]FIG. 1 shows an overall view of a foam encased mattress 1 made according to the method of the present invention.

[0023] The mattress 1 shown in this view is ready to be covered, such as by a quilted and/or decorative covering, marked, labeled, or finally prepared in some other way before sale. The finally prepared foam encased mattress 1 can be paired with a boxspring of any type or configuration, in the ordinary manner of the bedding art. In addition, the mattress 1 can be provided with a pillow-top in order to provided the maximum amount of comfort and restful sleep.

[0024] The foam encased mattress 1 can be made in any size, including standard bedding sizes, such as king size, California king size, queen, size, twin size, etc. according to the method of the present invention, simply by desirably shaping the major component parts, as will be discussed later. Desired firmness of the mattress 1 is selected by choosing any desired firmness of the innerspring unit 35, which will be discussed with reference to FIGS. 2 and 3.

[0025] Steps for assembling the foam encased mattress 1 according to the present invention will now be discussed with reference to FIGS. 2 and 3.

[0026]FIG. 2 shows a view of a foam housing 10 which provides the basic structure and shape for the foam encased mattress 1. The housing 10 also serves to completely enclose an innerspring unit 35. After assembly of the foam housing 10, the housing can be covered by a quilted cover 50, or any other decorative covering or pillow-top, as shown and discussed with reference to FIG. 5.

[0027] The foam housing 10 comprises only a few component parts, namely, a left side rail 12, a right side rail 14, a foot rail 15, a head rail 16, a bottom foam layer 42, and a top foam layer 46. Top foam layer 46 is clearly shown in FIG. 3.

[0028] Rails 12, 14, 15, 16 are each parallelepipedly shaped and made of high density polyurethane foam, such as manufactured by Foamex Corporation in Linwood, Ill. Alternatively, any foam having a high indent load deflection (ILD) would be satisfactory for use as rails 12, 14, 15, and 16.

[0029] Each rail 12, 14, 15, and 16 typically measures 4 inches (10 cm) in thickness. Side rails 12, 14 are equal in length and width, and their length is chosen to correspond to the length of the size of mattress desired. For instance, if it is desired to make a regular king size mattress, the length of rails 12, 14 should be 78.5 inches (200 cm), and if it is desired to make a queen size mattress, then the length of side rails 12, 14 should be 78.5 inches (200 cm), and so forth and so on for other mattress sizes desired.

[0030] Similarly, the dimensions of foot rail 15 and head rail 16 are equal, each having a typical thickness of 4 inches (10 cm). The width of foot rail 15 and head rail 16 is chosen to correspond to the width of the size of mattress desired. In the case of a regular king size mattress the width would be 74.5 inches (190 cm), and for a queen size mattress, the width would be 58.5 inches (149 cm), and so forth and so on for other sizes mattress sizes desired.

[0031] Assembly of the foam encased mattress I proceeds in two general stages. The first stage involves construction of the housing 10 which is made by securely joining together side rails 12, 14, foot rail 15, head rail 16, and bottom foam layer 42. This stage of assembly defines the overall size and shape of the completed mattress.

[0032] The second general stage involves placing the innerspring unit 35 within the then formed housing 10 and sealing the housing, with the innerspring unit firmly located therein, by securing top foam layer 46 to the surface of the joined together rails 12, 14, 15, 16, as will be discussed later.

[0033] Assembly of the foam housing 10 takes place on top of a planar surface, such as a table, that is large enough to support the intended overall dimensions of the completed foam encasement innerspring mattress 1. For instance, if the completed mattress is to be regular king-size, then the planar surface must be at least 74.5 inches by 78.5 inches (190 cm by 200 cm), which are the dimensions of a regular king size mattress, if the completed mattress is intended to be queen-size, then the planar surface must be at least 58.5 inches by 78.5 inches (149 cm by 200 cm), which are the dimensions of a queen size mattress, and so forth and so on for any other size mattress desired.

[0034] In assembling the housing 10, left side rail 12 and right side rail 14 are placed on the planar surface in spaced apart and parallel relation. Side rails 12, 14 are positioned so that each one is standing edgewise on the flat planar surface, meaning that their respective height from the planar surface will define the depth of the completed housing 10. The height dimension of the foot rail 15 and head rail 16 is the same as height dimension of the side rails 12, 14, which is typically 5-½ inches (13.75 cm). Thus, the housing 10 will take on the form of a symmetrical and planar unit when completed.

[0035] The next step in the assembly process is to position foot rail 15 and head rail 16, also standing edgewise on the flat planar surface, in registration with the ends of the parallel-standing side rails 12, 14. Rails 15 and 16 designate the foot of the mattress and the head of the mattress, respectively.

[0036] An adhesive suitable for joining together the material of which the rails 12, 14, 15, and 16 are made is provided to securely cement the foot end of the side rails 12, 14 to the foot rail 15, and the head end of the side rails 12, 14 to the head rail 16.

[0037] A double-sided adhesive tape, such as 9692, 9695 or 6035, all of which are manufactured by 3M is found to be suitable for the fastening function. However, any other type of fast-setting adhesive, suitable for reliably and securely fastening together pieces of the foam material used for the rails, will serve the function of joining the rails together. Moreover, any other reliable fastening techniques, such as stitching or hook and loop fasteners, may be employed as well. The adhesive tape has a width that is equal to or less than the width of the rails 12, 14, 15, and 16, and is provided in individual strips having lengths that are complementary to the length of each of the rails.

[0038] The double-sided adhesive tape has a first side having an adhesive surface and a second side having and adhesive surface. Each side is covered by a disposable peel-away backing, which covers the respective first and second adhesive surfaces of the tape until ready for use. When ready for use, the peel-away backing is removed from the respective side, thereby exposing the adhesive surface thereunder. The then exposed adhesive surface is ready for joining the components of the housing 10.

[0039] Foot rail 15 is fastened to the foot end of left side rail 12 by a strip 52 of the adhesive tape, and foot rail 15 is fastened to the foot end of the right side rail 14 by a strip 53 of the adhesive tape. To fasten head rail 15 to the head end of left side rail 12 a strip 54 (not shown) of the adhesive tape is applied to the head end of left side rail 12. A strip 55 of the adhesive tape is applied to the head end of right side rail 14. Details of these steps will be discussed with reference to FIG. 3.

[0040] A strip 18 (not shown) is attached to the uppermost surface of left rail 12 by exposing a first adhesive surface of the strip 18 and pressing the then exposed adhesive surface to the left rail 12, whereupon the strip 18 is securely fastened thereto by application of firm smooth and continuous downward pressure, thereby adhering the strip 18 to the surface of rail 12. a strip 20 is attached to the uppermost surface of right rail 14 by exposing a first adhesive surface of the strip 20 and pressing the then exposed adhesive surface to the right rail 14, whereupon the strip 20 is securely fastened thereto by application of firm, smooth and continuous downward pressure, thereby adhering the strip 20 to the surface of the rail 14.

[0041] Similarly, a strip 26 (not shown) is attached to the uppermost surface of foot rail 15 by exposing a first adhesive surface of the strip 26, and pressing the then exposed surface to the foot rail 15, whereupon the strip 26 is securely fastened thereto by application of firm, smooth and continuous downward pressure, thereby adhering the strip 26 to the surface of the rail 15. Another strip 30 (not shown) is attached to the uppermost surface of head rail 16 by exposing a first adhesive surface of the strip 30 and pressing the then exposed adhesive surface to the head rail 16, whereupon the strip 30 is securely fastened thereto by application of firm, smooth and continuous downward pressure, thereby adhering the strip 30 to the surface of the rail 16.

[0042] In preparation to receive the bottom foam layer 42 onto rails 12,14,15, and 16, the peel away backing is removed from the second adhesive side of tape strips 18, 20, 26, and 30, thus exposing the respective adhesive surfaces thereunder.

[0043] Bottom foam layer 42 is then positioned over the exposed adhesive surface of tape strips 18, 20, 26, and 30 attached to each of the rail pieces 12, 14, 15, and 16 and in registration therewith, and the bottom foam layer 42 is securely adhered to each adhesive tape piece by application of firm, smooth and continuous downward pressure along the entire perimeter formed by rails 12, 14, 15, and 16.

[0044] Bottom foam layer 42 is a planar sheet of polyurethane foam, provided in a thickness of 2 inches (5 cm). Layer 42 is sized and shaped to align with and be congruent to the outer dimension of the rail pieces 12, 14, 15, and 16, as shown in FIG. 2.

[0045] After this stage of completion, the housing 10 is flipped over to expose a cavity made up of the inner walls of the joined together left side rail 12, right side rail 14, foot rail 15, head rail 16, and the bottom layer foam 42.

[0046] A first netting layer 44 is placed in the bottom of the housing 10 so as to completely line the cavity in the housing formed by the joined rails 12, 14, 15, and 16, and bottom foam layer 42.

[0047] Next, innerspring unit 35 is firmly seated in the housing 10 within the space defined by the inner walls of the rails 12, 14, 15,16, and the bottom foam layer 42, on top of bottom netting 44. The cavity in the housing 10 is the same length, width and height as the innerspring unit 35. Therefore, the innerspring unit 35 is completely contained and nestled within the cavity.

[0048] Innerspring unit 35 is typical in design and construction to an inner spring unit found in other types of inner spring mattress. In the alternative, the innerspring unit 35 can be specially designed and manufactured for incorporation in to the foam encased mattress 1 of the present invention.

[0049] The innerspring unit 35 is selected for use in the mattress 1 based upon any selected design criteria for the mattress, such as firmness, durability, cost, etc. The innerspring unit 35 includes springs 38 and any necessary structural elements for holding the springs in place. The innerspring unit 35 is further provided with spacers 36 that serve to increase the overall length to create a mattress in a desired extra long, also referred to as simply “XL” size. However, the speacers 36 are not required on all mattress sizes. lnnerspring unit 35 is a unitary piece that is positioned within the housing 10 as a whole. Although innersprings 38 are depicted as coil springs in FIGS. 3, 4 and 5, any type of resilient element will function suitably well in the unit 35, according to the present invention. Such other types of resilient elements for use in the innerspring unit 35 include any bedding spring elements that may be found in the bedding art.

[0050] Thus, the first general stage is completed.

[0051]FIG. 3 shows further details of the assembly and construction of the foam encased mattress 1. The second general stage begins once the housing 10 has been completed and the innerspring unit 35 and netting layers 44, 45 have been positioned as discussed above with reference to FIG. 2, wherein a top foam layer 42 is provided to seal the housing 10 and enclose the innerspring unit 35 and netting layers 44, 45 within the housing. Top foam layer 46 is a planar sheet of polyurethane foam, provided in either a 1 inch (2.5 cm) thickness or a 2 inch (5 cm) thickness. Top foam layer 46 is sized and shaped to align with and be congruent to the outer dimension of the rail pieces 12, 14, 15, and 16, as shown in FIG. 3.

[0052] Top foam layer 46 is positioned over the exposed adhesive portion of tape strips on each of the rail pieces 12, 14, 15, and 16 in registration therewith. In preparation to receive the top foam layer 46 onto the rails 12, 14, 15, and 16, the peel away backing is removed from the second adhesive side thus exposing the adhesive surface thereunder. Top foam layer 46 is then positioned over the exposed second adhesive surface of tape strips 22, 24, 28, and 32 on each of the rail pieces 12, 14, 15, and 16 respectively, and in registration therewith. Top foam layer 46 is securely adhered to the second adhesive surfaces of tape strips 22, 24, 28, and 32 by application of firm, smooth and continuous downward pressure along the entire length of each tape strip.

[0053] Adhesive tape strip 52 is attached to the foot end of left side rail 12 by exposing a first adhesive surface of the tape strip and pressing the exposed adhesive surface to the foot end of left side rail 12, whereupon the strip 52 is securely fastened to the foot end by application of firm, smooth and continuous lateral pressure, thereby adhering the strip 52 to the foot end. Then, the backing is removed from the second adhesive side of the strip 52 to expose the adhesive surface thereunder.

[0054] Foot rail 15 is bought into registration with the foot end of left side rail 12 and is securely adhered thereto by the exposed second adhesive surface via application of firm smooth and continuous lateral pressure along the entire length of the tape strip 52.

[0055] Peel away backing of the double-sided adhesive tape is designated as reference numeral 25 in FIG. 3. Although only shown with reference to foot rail 15 in the Figure, it is to be understood that all tape pieces are provided with a similar peel-away backing.

[0056] Adhesive tape strip 53 is attached to the foot end of right side rail 14 by exposing a first adhesive surface of the tape strip, and pressing the exposed adhesive surface to the foot end of right side rail 14, whereupon the strip 53 is securely fastened to the foot end by application of firm smooth and continuous lateral pressure, thereby adhering the tape strip to the foot end. Then, the backing is removed from the second adhesive side of strip 53 to expose the adhesive surface thereunder. Foot rail 15 is securely adhered to the exposed second adhesive surface by application of firm, smooth and continuous lateral pressure along the entire length of the tape strip 53.

[0057] Adhesive tape strip 54 (not shown) is attached to the head end of left side rail 12 by exposing a first adhesive surface of the tape strip, and pressing the exposed adhesive surface to the foot end of left side rail 12, whereupon the strip 54 is securely fastened to the head end by application of smooth and continuous lateral pressure, thereby adhering the tape strip 54 to the head end. Then, the backing is removed from the second adhesive side of the strip 54 to expose the adhesive surface thereunder. Head rail 16 is securely adhered to the exposed second adhesive surface by application of firm, smooth and continuous lateral pressure along the entire length of the tape strip 54.

[0058] Similarly, adhesive tape strip 55 is attached to the head end of right side rail 14 by exposing one adhesive surface of the tape strip, and pressing the exposed adhesive surface to the head end of right side rail 14, whereupon the strip 55 is securely fastened to the head end by application of firm smooth and continuous lateral pressure, thereby adhering the tape strip 55 to the head end. Then, the backing is removed from the second adhesive surface of the strip 55 to expose the adhesive surface thereunder. Head rail 16 is securely adhered to the exposed second adhesive surface by application of firm, smooth and continuous lateral pressure along the entire length of the tape strip 55.

[0059] As discussed with respect to FIG. 2 above, double-sided adhesive tape strips 18, 20, 26, and 30 are applied to the bottom surface of each of the side rails 12, 14, foot rail 15, and head rail 16, the adhesive tape strips 18, 20, 26, and 30 fasten the bottom foam layer 42 to the respective rails. Double-sided adhesive tape strips 22, 24, 28, and 32 are applied to the top surface of each of the side rails 12, 14, foot rail 15, and head rail 16, in the same manner as adhesive tape was applied to the bottom surface of the rails 12, 14, 15, and 16. The adhesive tape strips 22, 24, 28, and 32 fasten the top foam layer 46 to the respective rails.

[0060] A sectional view of the left rail 12 of the mattress shown in FIG. 4. The sectional view and the following discussion of left rail 12 is representative of the structure and arrangement of the remaining rails 14, 15 and 16.

[0061] A top netting layer 45 is placed on top of the innerspring unit 35 once it has been securely placed within the housing 10, but before the top foam layer 46 is put into place. Top netting layer 45 is placed over the top of the innerspring unit 35 so as to completely cover it. Excess extending to the edge of bottom netting layer 44 and extending to the edge of top netting layer 45 is tucked around the sides of the inner spring unit 35.

[0062] Netting layers 44, 45 are each made of a plastic, such as polypropylene, and are provided to prevent foam layers 42, 46 from migrating into the coils 38 of the innerspring unit 35. Instead of using netting made of a plastic, any material, suitable for the purpose of preventing migration of foam layers 42, 46 into the coils 38 of the innerspring unit 35 could be used in construction of the mattress 1.

[0063] The location and disposition of the edges of netting layers 44, 45, which are unconnected, simply fold around innerspring unit 35, tuck into and occupy any residual space found between the inner wall of the rails 12, 14, 15, and 16 and the innerspring unit 35.

[0064]FIG. 5 is a top plan cutaway view of the completed mattress 1, wherein all components required for assembly are shown. Side rails 12, 14, foot rail 15, and head rail 16 are positioned and secured together with respect to bottom foam layer 42 and top foam layer 46. Bottom and top netting layers 42, 44 are in place within the cavity formed by the rails 12, 14, 15, and 16 and the bottom foam layer 42, with the innerspring unit 35 located therein.

[0065] A final and decorative cover 50 encases the mattress 1, and the covering 50 can be a comfortable quilting or any other desired covering. A pillow-top can also be provided for maximum comfort.

[0066] The foam encased mattress 1 can be manufactured either in a one-sided version or a two-sided version. For the two-sided mattress, a 1 inch (2.5 cm) layer of polyurethane is provided for each of the layers 42, 44. For the one-sided version of the mattress 1, top layer 44 is a 1 inch (2.5 cm) thick layer of polyurethane, while a 2 inch (5 cm) thick layer of polyurethane is provided for the bottom layer 42. The one-sided version eliminates the need to “flip” or “turn” the mattress, and hence is often referred to as a “never-turn-mattress”, or is sometimes called a “non-flip mattress.”

[0067] The mattress 1 is not limited to the ordinary rectangular shape of a traditional flat bed mattress, but can be formed in any desired shape, such as round, oval or triangular, simply by varying the shape of the main component parts. For instance if it is desired to make the foam encased mattress 1 a round shape, all that need be done is shape the rails 12, 14, 15, and 16 so that they form a complete circle when joined together. Specific additional method steps would for instance include, forming the top and bottom foam layers 42, 46 in a congruently round form, and providing the innerspring unit 35 in a similarly round shape. The circular housing formed by the joined rails 12, 14, 15, and 16 and the round foam layers 42, 46 should be dimensioned to accommodate the similarly round innerspring unit. Further completion of such round mattress could proceed as described above and shown in FIGS. 2 and 3.

[0068] Even though the method of the present invention is herein discussed as a series of sequential steps, it can easily be understood from the Figures and from the description, that the method steps necessary to make the foam encased mattress I of the present invention can be performed in various orders, or as a combination of steps, with very little effort and in a time-efficient manner.

[0069] Although modifications and changes may be suggested by those skilled in the art to which this invention pertains, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications that may reasonably and properly come under the scope of their contribution to the art. 

What is claimed is:
 1. A method of making a foam encased mattress, the method of comprising the steps of: building a foam housing, including the steps of: positioning first and second side rail pieces on edge and in parallel, spaced-apart alignment, applying adhesive to top edge surfaces of said side rails, positioning head rail pieces, and applying adhesive and adhering the head rail thereto, positioning foot rail pieces applying adhesive and adhering foot rail thereto, applying adhesive to top surfaces to said first and second side rail pieces, said head rail and said foot rail; positioning a first planar layer over said adhesive in registration with said side rail pieces, said head rail and said foot rail, and adhering said planar layer hereto respectively; flipping over said foam housing; positioning netting within said foam housing; positioning an innerspring unit within said foam housing; applying adhesive to top surfaces of said first and second side rail pieces, said head and said foot rail; positioning a second planar layer over said adhesive in registration with said side rail pieces, said head rail and said foot rail, and adhering said planar layer thereto respectively.
 2. The method of claim 1, wherein said adhesive is a double-sided adhesive tape.
 3. The method of claim 1, further comprising the step of: providing said foam encased mattress with a pillow-top.
 4. The method of claim 1, further comprising the step of: covering said foam encased mattress with a quilted cover.
 5. A foam encased mattress, having a foam housing, the mattress comprising: first and second side rails, a head rail, and a foot rail, said rails joined together in respective planar registration with one another to form a cavity; a first planar foam layer disposed over and joined to a first surface of said foam housing; a second planar foam layer disposed over and joined to a second surface of said foam housing; and an innerspring unit, whereby said innerspring unit is sealed within said cavity by said rails and said planar foam layers.
 6. The foam encased mattress of claim 5, wherein said rails and said foam layers are joined together by double-sided adhesive tape.
 7. The foam encased mattress of claim 6, further comprising a pillow-top.
 8. The foam encased mattress of claim 7, further comprising a quilted cover. 